I had the Coronavirus back around Thanksgiving.  No fun. Three days in the hospital later I was on the mend and doing great.  What was a low 81% reading on the oxygen saturation oximeter back then was a solid 99% at a checkup today.
So yes, things were going well ...and then I got the vaccine - Moderna style and it wacked me for two days like I had COVID all over again!  It was short lived but my arm where I received the vaccine was what we used to call a hurtin' unit !  That phenomenon has a name and it is as obvious as it gets.  Yahoo News reports that is been dubbed "COVID arm".
 
"Officials at the Centers for Disease Control and Prevention (CDC) have long stipulated that arm pain as well as swelling and redness are expected side effects of any vaccine, among other temporary symptoms. However, some people are getting a more noticeable reaction at the injection site that’s now being referred to as “COVID arm.”
The symptoms of COVID arm can turn up long after your first shot, in some cases up to a week afterwards.  In my case it was the next day and running for about four days which was two days more than any of my other post vaccine symptoms.
"An early study in 2020 looked specifically at the Moderna vaccine and found some people experienced redness, swelling, tenderness, or even a skin rash eight days or more after getting the shot.  Researchers also found less than one percent of individuals who got the Moderna vaccine developed a raised, itchy rash, that may even appear as a lesion in some cases, afterward."
Time has shown that these kind of symptoms are not severe and are easily treated.  I didn't get itchiness or a rash but it was quite painful and I couldn't / didn't want to lift or move my arm much over the next few days.  Keep that in mind if / when you get you shot.  Get it in your none dominant arm so at least you can eat!
The experts says that if you don’t have any prior medical conditions that would prevent you from doing so, you should take ibuprofen or acetaminophen to lessen arm pain, and antihistamines to reduce itchiness or discomfort related to any rashes. You can also apply ice to your arm if it’s swollen.
One thing they say NOT to do is use antibiotics and they say see your doctor if you get a post vaccine fever, aches or fatigue.
It's easy for the "experts" to say, so they say it...but it is your decision... however "they" say experiencing COVID arm should NOT discourage you from receiving your second dose of the vaccine.  I'm not looking forward to it, but I plan to get it next week.